The present technology relates to an apparatus, a method, and a program for a 3D data analysis, and a fine particle analysis system. More specifically, the present technology relates to a 3D data analysis apparatus or the like that can display measurement data regarding fine particles using a 3D stereoscopic image and that can perform a data analysis of population information or the like using the image.
A fine particle measuring apparatus is known that introduces dispersion liquid of fine particles into a flow passage and that optically, electrically, or magnetically measures the fine particles, in order to analyze the fine particles including biological particles such as cells, microorganisms, and liposomes and composite particles such as latex particles, gel particles, and industrial particles.
As an example, there is a particle analyzer that judges composite particles in accordance with the sizes and the shapes. Parameters (variables) that can be measured by the particle analyzer include the elemental composition and the particle diameters of fine particles.
In addition, a flow cytometer (flow cytometry) is used for an analysis of biological particles. Parameters that can be measured by the flow cytometer include the forward-scattered light (FS), the side scattering (SS), the fluorescence (FL), and the impedance of fine particles. The forward-scattered light (FS), the side scattering (SS), and the fluorescence (FL) are used as parameters indicating the optical characteristics of cells and microorganisms (hereinafter simply referred to as “cells”) and the impedance is used as a parameter indicating the electrical characteristics of the cells.
More specifically, first, the forward-scattered light is light scattered at a small angle in a forward direction relative to an axis of laser light and composed of scattered light, diffracted light, and refracted light of the laser light generated on surfaces of cells. The forward-scattered light is mainly used as a parameter indicating the sizes of cells. Next, the side scattering is light scattered at an angle of about 90 degrees relative to the axis of the laser light and is scattered light of the laser light generated at granules and cores inside cells. The side scattering is mainly used as a parameter indicating the internal structures of cells. In addition, the fluorescence is light generated from a fluorochrome with which cells are labeled and is used as a parameter indicating whether or not there is a cell-surface antigen recognized by a fluorochrome-labeled antigen, the amount of nucleic acid with which a fluorochrome has been coupled, and the like. In addition, the impedance is measured by an electrical resistance method and used as a parameter indicating the volume of cells.
A data analysis apparatus is used that creates and displays a graph representing the characteristic distribution of cells in a cell population by plotting measured values of each cell while using these measurement parameters as axes in order to analyze measurement data of the flow cytometer. A one-dimensional distribution graph that uses one measurement parameter is also referred to as a histogram and created as a graph in which an X-axis represents the measurement parameter and a Y-axis represents the number of cells (count). In addition, a two-dimensional distribution graph that uses two measurement parameters is also referred to as a cytogram and created by plotting each cell in a coordinate plane in which one of the measurement parameters is represented by the X-axis and the other measurement parameter is represented by the Y-axis on the basis of its measured value.
By setting regions in a histogram or a cytogram, it is possible to obtain statistical data regarding cells existing in each region. As the statistical data, frequency distribution (population information) indicating the percentage of target cells included in a cell population is often used. The frequency distribution is calculated as the percentage of cells existing in each region set in the histogram or the cytogram relative to the entirety.
For example, when it is known that target cells indicate values equal to or larger than a certain value in a certain parameter, calculation of the distribution frequency of the target cells in a histogram is performed by dividing the histogram into two at the certain value along the X-axis. In doing so, the histogram is divided into a region (a region in which the target cells exist) equal to or larger than the certain value and a region (a region in which non-target cells exist) smaller than the certain value. With respect to each set region, the data analysis apparatus calculates the distribution frequency from the number of cells existing in each region. In addition, when a cytogram is used, calculation of the distribution frequency is performed by dividing the cytogram into four regions at certain values along the X-axis and the Y-axis. In doing so, the cytogram is divided into a region (a region in which the target cells exist) in which both the two parameters are equal to or larger than the certain values and regions (region in which non-target cells exist) in which either parameter is smaller than the certain value.
In PTL 1, “an analysis apparatus comprising measurement data obtaining means that obtains first, second, and third pieces of measurement data from an object to be analyzed, three-dimensional distribution graph creation means that creates a three-dimensional distribution graph indicating distribution of tangible components included in the object to be analyzed using the first, second, and third pieces of measurement data as axes, region setting means that sets a cut-off region in the three-dimensional distribution graph in such a way as to enable a change, and reference distribution graph creation means that creates at least either a two-dimensional distribution graph that uses the first and second pieces of measurement data as axes or a frequency distribution graph that uses the first piece of measurement data as an axis for tangible components belonging to the cut-off region set by the region setting means” is proposed (refer to Claim 9 of the literature). According to this analysis apparatus, a cut-off region can be set in a three-dimensional distribution graph while referring to a two-dimensional distribution graph (cytogram) and a frequency distribution graph (histogram) displayed together with the three-dimensional distribution graph. It is to be noted that the three-dimensional distribution graph of this analysis apparatus is displayed on a display in a planer manner and not viewed stereoscopically.
In relation to the present technology, a two-eye type stereo stereoscopic image technology (a 3D stereoscopic image technology) will be described. In the two-eye type stereo stereoscopic image, first, two images when an object is viewed by a right eye and a left eye are prepared. Next, while simultaneously displaying these images, an image for the right eye is presented only to the right eye and an image for the left eye is presented only to the left eye. In doing so, an image when the object is viewed in a three-dimensional space is reproduced and causes the user to stereoscopically view the object.
3D displays that enable stereoscopic vision mainly adopt (a) glasses methods, (b) naked eye methods, and (c) viewer methods. The (a) glasses methods further include anaglyph methods, polarizing filter methods, and time-division methods. In addition, the (b) naked eye methods include parallax barrier methods and lenticular methods, and the (c) viewer methods include stereoscope methods and head mount methods.